Method of treating undried organic nitrates and the like



UNITED sTAras' TENT cer cal WALTER OLSNELLINGQOF Annnnrown,PENNSYLVANIA, AssIenon rot'rnoaiin POWDER CQMZBANY, on NEW xonx, n. Y.,A CORPORATION on NEW YORK.

Specification of Letters Patent.

METHOD OF TREATING UNDRIED ORGANIC nr'rnarns AND THE LIKE. 1

No Drawing, Application filed March 16, 1920," Serial No. 366,390.Renewed January 21,1921. r-Serial No. 439,054. a

To all whom it may concern: 1

Be it known that I, WALTER O.- SNnLmNe, a citizen of the United States,and resldent of Allentown, Lehigh county, Pennsylvania, 7

5 have invented certain Improvements inthe Method of Treating UndriedOrganic Nitrates and the like, of which the following is aspecification." w V 'My invention relates to the manufacture v10 ofexplosives and similar materials which,

owing .to the manufacturing processes employed, are obtained in wetcondition, and the object of the invention is to provide a method forreducing the water content of such materials without drying. .While myinvention may be utilized in the manufacture of a number of materials, Ihave found it particularly useful as applied to the manufacture ofexplosives, and for purposes of specific illustration will describe itin connection with such manufacture.

In the manufacture of nitrocellulose, nitrostarchrand other solidorganic nitrates, said materials, following the nitration and washingprocesses, are in wet condition, and it has hitherto been the practiceto dry them before mixing with other ingredients toproduce commercial ormilitary explosives.

Even where it has been desired .to produce a wet finished explosive, thepreliminary:

drying process has been deemed necessary because of the undue amount ofwater'present with the organic nitrate following the washing process.While it is manifestly desirable to avoid the drying operation-byutilizing the nitrostarch or nitrocellulose in wet condition, as inthisway an important item of expense and danger is avoided, experiments haveshown that explosives of '40 proper sensitiveness cannot be made by themere mixing of salts with undried nitro starch or nitrocellulose. Forexample, ni-

trostarch after coming from the centrifuge andhaving its water contentreduced there- 7 '45 in tothe lowest obtainable amount, still containsan average of about 20% of moisture. If now such wet nitrostarch ismixed in equal parts with nitrate of'soda or with nitrate of ammonia thecompleted mix will still contain 10% of moisture, and this is higherthan the amount which such a mix' can contain and still detonate 'withsuch detonating caps as are commercially used. It is true that by usinga smaller amount'of the wet .nitrosta r ch, and a greater amount of thenitrate, mixtures having a lower wa- Patented A g. 2 1921.

ter content can be obtained. One part of wet nitrostarch may for examplebe mixed w1tl1' three parts of sodium nitrate, and-in this case if theinitial nitrostarch contained 20% of water the final mix will'containbut 5% of water. Such a mix is, however, quite as insensitive as themixture'previously described, and which contained 10% of water, for thereason that the amount of nitrostarch has bee-n reducedvin proportion"as the waterhas been reduced, thefirst mix-V ture containing 40% ofnitrostarch on a dry an explosive susceptible to detonation with,

the No. 6 or No- 7 detonators commonly used incommercial work.

I have discovered an inexpensive and convenient method by whichsensitive explosives may be obtained from organic nitrates withoutrecourse to thenormal drying op-,

eration. As an example of my invention, I will describe the method bywhich I make basis, and 10% of water, and the second mixa g anitrostarch explosive from nitrostarch icontaining 25% of water.

'I first prepare a concentrated solution ammonium nitrate and water,preferably usmg a solution contalnlng about 65% of dissolvedammoniumnitrate. I thoroughly mix my wet nltrostarch with such asolution, either bv mixing the wet nitrostarch with the solution andthen applying ce'ntrifugal force to remove the excess, or by,

an operation ofdisplacement. In any case I substitute a solution ofammonium nitrate for the water which is normally present in the wetmaterial.

As the result of this firststage of mypro-,

cedure, I obtain instead of nitrostarch wet l with 25% of'water.nitrostarch which contains 25% of a concentrated solution of ammoniumnitrate. present in the nitrostarch tends to dilute my original ammoniumnitrate solution, in or As the'water originally V ammonium nitrate, andmy nitrostarch con-v dinary procedure I obtain an absorbed solutioncontaining about 50% by we1ght of after moderate wringing.

If I now mix equal weights of the nltrostarch so prepared with ammoniumnitrate,

tains about 25% by weight of this solution,

I obtain a mixturewhich contains 87.5% of nitrostarch, 56257 of ammoniumnitrate,

and 6.25% of water. This mixture is sensitive to commercial detonators,and forms a highly desirableexplosiver I mayemploy 70% of my wetnitrostarch and 30% of ammonium nitrate, and in this case my finishedexplosive contains 52.5%- of mtrostarch,

38.7 5% of ammonium nitrate, and 8.7 5% of water, this explosive alsobeing sensitive to a commercial detonating cap.

Through treatment as described, my ammo-' nium nitrate solution becomesdiluted through the water taken up from the nitrostarch, and becomesimpoverished through the giving up to the nitrostarc'h of part of itsdissolvedammonium nitrate. Accordingly I may from time to time add moreammonium' nitrate,

and I may if necessary remove portions of the liquid from time to timeand concentrate same. Preferably I so adjust the moisture in my nitratedproduct that the amount of dis solved inorganic nitrate taken up by thenitrostarch or the nitrocellulose balances as nearly as possible theamount of Water given up to the bath. I

From theforegoing illustration it will be seen that while the liquidcontent of the explosive material is not reduced, the water content hasbeenreduced, a portion of the latter being replaced by. an ingredienthav ing a function in the finishing explosive. Obviously other inorganicoxidizing salts having a high solubility in water may be substituted forammonium nitrate, such, forexample, as calcium nitrate, or. ammonium orsodium chlorate or perchlorate. In the manufacture of some explosives,or other material, the displacing solution need not necessarily be thatof a salt performing any function in the finished product other than thedisplacing function the method in its broader aspect contemplating thereduction of the water or other liquid content of a wet material byreplacement by a concentrated solution of an inorganic salt. V

The solid salt which is admixed with the wet organic nitrate prepared asdescribed in organic nitrate.

originally present.in ;undr1ed nitrated starch thisapplication may ormay not be the same material of which a solution is used for displacingthe .water originally present in the For example, the water may bedisplaced by means of a concentrated solution of; ammonium nitrate, andthe wet nitrostarch so prepared may then be mixed with dry ammoniumnitrate or the nitrated starch prepared as described may be mixed withdry sodium nitrate, or with dry ammonium perchlorate'or with any othersuitable dry salt or mixture of dry salts. Instead of a solution ofammonium nitrate or other inorganic salt I mayuse a concentratedsolution of any solid body havinghigh solubility inwater. v

Iclaim:

1. The method of treating .wet materials to reduce the water contentwithoutdrying which comprises the step of replacing a portion of saidWater by a concentrated solution of a solid body having high solubilityin water. V

2. In the method of manufacturing explosives and the like containingasolid organic nitrate, the stepwhich comprises displacing water presentin theundried organic nitrate by a concentratedsolution of 1 aninorganic nitrate.

3. Themethod of manufacturing Wet explosives containing an organicnitrate and an inorganic salt which comprises the step of displacingwater originally associated with said organic nitrate by a solutionlofsaid inorganic salt. i

V 4. The processof making a wet explosive WALrE o. SNELLING.

